I have an over abundance of field load RST 12 and 16 gauge lead and bismuth shotshells I would like to list in the “for sale” section here. Any advice shipping these by the box and flat? Ship USPS? Regulations?
Go to BPI's website. Read their instructions for shipping ammunition to them for testing. Copy their Haz Mat label, provided for that purpose.
I have always used Fed Ex Ground (You must specify ground shipping with any carrier). They just happened to have a friendly counter at my last address. UPS or Speedee should work just as well if they have good counter workers. USPS is out, as noted above.